static CharEscaper createSimpleCharEscaper(ImmutableMap<Character, char[]> replacementMap) {
    return new CharEscaper() {
      @Override
      protected char[] escape(char c) {
        return replacementMap.get(c);
      }
    };
  }

  // A trivial non-optimized escaper for testing.
  static UnicodeEscaper createSimpleUnicodeEscaper(ImmutableMap<Integer, char[]> replacementMap) {
    return new UnicodeEscaper() {

  }

  static void checkExactMatches(CharMatcher m, char[] chars) {
    Set<Character> positive = Sets.newHashSetWithExpectedSize(chars.length);
    for (char c : chars) {
      positive.add(c);
    }
    for (int c = 0; c <= Character.MAX_VALUE; c++) {
      assertFalse(positive.contains(Character.valueOf((char) c)) ^ m.matches((char) c));
    }
  }

  static char[] randomChars(Random rand, int size) {

      chars.add(randomNonAlpha());
    }
    Collections.shuffle(chars, random);
    char[] array = Chars.toArray(chars);
    this.testString = new String(array);
  }

  private char randomAlpha() {
    return ALPHA.charAt(random.nextInt(ALPHA.length()));
  }

  private char randomNonAlpha() {
    return NONALPHA.charAt(random.nextInt(NONALPHA.length()));
  }

  @Benchmark

        }
    }

    @Override
    public String toString() {
        final int len = this.length / 2 - (this.zterm ? 1 : 0);
        final char[] ca = new char[len];
        for (int i = 0; i < len; i++) {
            ca[i] = (char) this.buffer[i];
        }
        return new String(ca, 0, len);
    }

    /**
     * Performs constant-time comparison of two char arrays to prevent timing attacks.
     * This method always compares the full length of both arrays, regardless of when
     * differences are found, making the execution time independent of the position
     * of differing characters.
     *
     * @param a first char array to compare
     * @param b second char array to compare
     * @return true if arrays are equal, false otherwise

    }
  }

  public void testUtf8() {
    char[] charsA = new char[128];
    char[] charsB = new char[128];

    for (int i = 0; i < charsA.length; i++) {
      if (i < 100) {
        charsA[i] = 'a';
        charsB[i] = 'a';
      } else {
        // Both two-byte characters, but must be different
        charsA[i] = (char) (0x0180 + i);
        charsB[i] = (char) (0x0280 + i);
      }
    }

     * @return a hexadecimal string representation of the value, padded to the specified size
     */
    public static String toHexString(final int val, final int size) {
        final char[] c = new char[size];
        toHexChars(val, c, 0, size);
        return new String(c);
    }

    /**
     * Converts a long value to a hexadecimal string representation with specified padding.
     *

  }

  static void checkExactMatches(CharMatcher m, char[] chars) {
    Set<Character> positive = Sets.newHashSetWithExpectedSize(chars.length);
    for (char c : chars) {
      positive.add(c);
    }
    for (int c = 0; c <= Character.MAX_VALUE; c++) {
      assertFalse(positive.contains(Character.valueOf((char) c)) ^ m.matches((char) c));
    }
  }

  static char[] randomChars(Random rand, int size) {

    // Exhaustively check all mappings (an int index avoids wrapping).
    for (int n = 0; n < replacementArray.length; n++) {
      char c = (char) n;
      String expected = map.get(c);
      if (expected == null) {
        assertThat(replacementArray[n]).isNull();
      } else {
        assertThat(new String(replacementArray[n])).isEqualTo(expected);
      }
    }
  }

      int h1 = seed;
      int i = 0;
      int len = 0;

      // This loop optimizes for pure ASCII.
      while (i + 4 <= utf16Length) {
        char c0 = input.charAt(i);
        char c1 = input.charAt(i + 1);
        char c2 = input.charAt(i + 2);
        char c3 = input.charAt(i + 3);
        if (c0 < 0x80 && c1 < 0x80 && c2 < 0x80 && c3 < 0x80) {
          int k1 = c0 | (c1 << 8) | (c2 << 16) | (c3 << 24);